Internal combustion engines, in particular of the constant pressure cycle type



March 19, 1963 R. GEORGES 3, 8

INTERNAL COMBUSTION ENGINES, IN PARTICULAR OF THE CONSTANT PRESSURE CYCLE TYPE Filed Feb. 6, 1962 3,081,754 INTERNAL COMBUSTION ENGINES, IN PARTECU- LAR OF THE CONSTANT PRESSURE CYCLE TYPE Raymond Georges, 67 Avenue Foch, Paris 16, France Filed Feb. 6, 1962, Ser. No. 171,432 Claims priority, application France Feb. 14, 1961 1 Claim. (Cl. 123-4116) The present invention relates to internal combustion engines of the reciprocating piston type. It is more espe cially but not exclusively concerned with engines of this type working with a constant pressure cycle and in particular with diesel engines, particularly in the case of light engines intended to run at high speed.

The object of my invent-ion is to provide an engine of this type which is better adapted to meet the requirements of practice than those known up to now, and in particular wherein the valve seats have a longer life.

In such engines the cylinder head body is made of a light metal or alloy which is a good conductor of heat and cylinder head linings are fitted in said cylinder head body, said linings being made of a metal or alloy, such for instance as a refractory metal or an austenitic steel, which is not as good a conductor of heat as the material forming the cylinder head body but as high mechanical resistance qualities at high temperatures, for instance averaging 900 C. and even more.

My invention consists in providing, in such cylinder head linings, apertures corresponding to the locations of the valves, the seats of said valves being made independent of the corresponding cylinder head linings and being fixed directly in the cylinder head body, which facilitates their cooling.

A preferred embodiment of my invention will be hereinafter described with reference to the accompanying drawing given merely by way of example and in which the only FIGURE shows, in axial section and with parts cut away, a diesel engine made according to the invention.

This engine comprises a crankcase 1 in which is mounted a cylinder head body or unit 2 made of a light metal which is a good conductor of heat, for instance aluminum.

In order to keep a Wall temperature as high as possible in every combustion chamber of this engine, I make use of cylinder head linings 3 fitted in the respective cylinders. Advantageously, as shown, every cylinder head lining 3 is kept in position by the fixation of the cylinder head body 2 on crankcase 1. Said cylinder head linings are made of a metal or alloy, such for instance as a refractory metal or austenitic steel, which is not as good a conductor of heat as the light metal or alloy of the cylinder head body 2, but having, at high temperature (for instance at tempera tures averaging 900 C. and even higher) mechanical resistance qualities much higher than those of said light metal or alloy. These cylinder head linings 3 thus constitute thermal screens with respect to the cylinder head body 2 which is thus protected against any risk of deformation at the temperatures of operation of the engine.

Patented Mar. 19, 1963 ice According to the main feature of this invention, I provide in said cylinder head linings 3, apertures corresponding to the position of the valves 4 of the engine, the seats 5 of said valves being made independent of said cylinder head linings and being secured directly in the cylinder head body 2.

Thus the heat developed in the valve seats 5 can be easily evacuated through the cylinder head body 2, made of a light metal or alloy which is a good conductor of heat. This evacuation of heat may be improved by the circula tion of a cooling fluid (water or air) through passages 6 provided for this purpose in said cylinder head body.

A lowering of the temperatures of the valves seats 5 which is of course desirable to increase the life of these parts, may be further improved by providing in said seats, as shown in dotted lines, a cavity 7 which is filled with sodium in a manner well known in the art.

Valve seats 5 may be made of any suitable metal or alloy, for instance a special bronze, and they may be fitted in the cylinder head body in any suitable manner for instance either by screwing, as shown by the drawing, or by a force fit.

In a general manner, while I have, in the above description, disclosed What I deem to be a practical and efiicient embodiment of my invention, it should be well understood that I do not Wish to be limited thereto as there might be changes made in the arrangement, disposition and form of the parts Without departing from the principle of the present invention as comprehended within the scope of the accompanying claim.

What I claim is:

An internal combustion engine which comprises, in combination, a cylinder, a piston fitting slidably in said cylinder for reciprocating movement therein, a cylinder head body made of a light metal material which is a good conductor of heat, a cylinder head lining fitted in said cylinder head body, said cylinder head lining made of a material which is not so good a conductor of heat as said first mentioned material and has higher mechanical resistance than said first mentioned material, said cylinder head lining having apertures formed therein, valve seats mounted in said cylinder head body in register with said apertures, valves mounted to cooperate with said valve seats respectively, each of the valve seats being provided with an internal cavity, and sodium filling said cavity.

References (Iited in the file of this patent UNITED STATES PATENTS 1,693,520 Kondo Nov. 27, 1928 1,701,550 Woolson Feb. 12, 1929 1,857,077 Adamson May 3, 1932 1,958,004 Jehle May 8, 1934 2,362,622 Fischer Nov. 14, 1944 2,369,025 Cummings Feb. 6, 1945 2,600,529 Gregory June 19, 1952 2,716,969 Lang Sept. 6 1955 

